Tyre size question

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Dec 31, 2006 | 05:41 AM

Flowerfred

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On my style 124's, the rear tyres measure 275-35-18, the front ones 245-40-18.
I presume the first number is the width, the middle one the height of the sidewall, the last on the diameter of the rim.

So how come one is 35, the other one 40? What am I missing?

Dec 31, 2006 | 06:15 AM

colejl

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Quote:

Originally Posted by Flowerfred' post='372576' date='Dec 31 2006, 02:41 PM

The sidewall is a percentage function of the width. So the sidewall of the 245's are 98mm (40% of 245mm) and the 275's are 96mm. (They would of been 110mm if 40% profile!)

Dec 31, 2006 | 06:24 AM

Flowerfred

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Cheers for that!

So we have an absolute size in metric, a relative size and an absolute size in emperial measurements..

Mensa stuff really

Dec 31, 2006 | 07:13 AM

KAF

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Quote:

Originally Posted by Flowerfred' post='372579' date='Dec 31 2006, 03:24 PM

Cheers for that!

So we have an absolute size in metric, a relative size and an absolute size in emperial measurements..

Mensa stuff really

No, there is a quite simple and logical explanation, it's um...........................er................... ......well.......................sort of.........................like................... ......and......................................... ........................doh !. :'(